The present invention discloses a shorted monopole antenna comprising a radiating portion comprises a first metal portion and a second metal portion and is located on the dielectric substrate, without overlapping with the ground plane. The first metal portion comprises a coupling section formed by bending the front portion of the first metal portion into two adjacent sections with a coupling gap. A first end of the feeding portion is electrically connected to the first metal portion. A second end of the feeding portion is the antenna's feeding point. The shorting portion is disposed on the dielectric substrate, without overlapping with the ground plane. A first end of the capacitive element is electrically connected to the antenna's feeding point. A second end of the capacitive element is electrically connected to a source.